1. Field of the Invention
The present invention relates to a mechanical pencil and more particularly to a mechanical pencil having a sleeve capable of writing pressure regulation and a lead cartridge functioning as a lead pipe.
2. Description of the Prior Art
In writing with a conventional mechanical pencil, it is necessary to take out leads from a lead case and replenish the mechanical pencil with leads by putting leads one by one into the lead pipe, when the lead of the mechanical pencil is exhausted. Such a lead refilling work is troublesome and soils the fingers.
A mechanical pencil having an excessive writing pressure absorbing function needs a second spring for excessive writing pressure absorption in addition to a first spring for projecting a lead, and hence the construction is complicated and the assembling work is troublesome. The applicant of the present invention proposed a mechanical pencil having a sleeve capable of regulating writing pressure, in Utility Model Application No. Sho 57-67850, to overcome the disadvantages of the conventional mechanical pencil.